Risk-stratified approach to hybrid transcatheter-surgical palliation of hypoplastic left heart syndrome.

We prospectively employed a risk-stratified approach to first-stage palliation of hypoplastic left heart syndrome. High-risk features included severe tricuspid insufficiency, severe right ventricular dysfunction, a severely restrictive or intact atrial septum, an ascending aortic diameter < or = 2 mm, late presentation, weight < 2 kg, or significant extracardiac issues, Infants without high-risk features underwent a Norwood procedure (with Sano modification), whereas infants with high-risk features underwent a hybrid procedure consisting of bilateral pulmonary artery banding, ductal stenting, and atrial septostomy or a Norwood/Sano. Operative survival for 10 infants without high-risk features undergoing a Norwood/Sano procedure was 90%. Operative survival for 5 infants with high-risk features undergoing hybrid palliation was 100%, compared to 29% in 7 infants with high-risk features undergoing the Norwood/Sano procedure. Although only short-term data are available, this hybrid palliative procedure may have a role for infants with hypoplastic left heart syndrome and high-risk features.

Influence of congenital heart disease on mortality after noncardiac surgery in hospitalized children.

OBJECTIVE: To evaluate the incremental risk of congenital heart disease on mortality after noncardiac surgery in children. DESIGN: We reviewed the clinical information network database of the University Hospital Consortium for the period January 1, 1993, through December 31, 1996, and identified 191 261 patients <18 years old having 1 or more noncardiovascular surgical procedures. Of these patients, 6.5% had a diagnosis of congenital heart disease. Patients having ambulatory surgery are excluded from this database. Short-term (1-, 2-, and 3-day) and 30-day mortality were compared, as well as mortality for neonates, infants (31 days to 1 year), and older children (1-17 years); mortality for the 100 most common surgical procedures, mortality for 10 relatively minor surgical procedures, and mortality in subgroups of patients with minor versus severe cardiac diagnoses. RESULTS: Short-term and 30-day mortality was increased in the patients with congenital heart disease patients (30-day mortality odds ratio 3.5; 95% confidence limit, 3.2-3.9). Mortality was also increased in patients with congenital heart disease in the 2 youngest age groups, for the 100 most common operations, and for 10 relatively minor operations. Children with more severe heart disease diagnoses had higher mortality than did children carrying less serious cardiac diagnoses. CONCLUSION: A diagnosis of congenital heart disease adds significant incremental risk of mortality in children requiring inpatient noncardiovascular surgery. This outcome difference is present for both minor and major surgical procedures, and regardless of whether mortality is measured at 1, 3, or 30 days. The incremental risk is greatest in neonates and infants where the presence of congenital heart disease is associated with a 2-fold increase in mortality from noncardiac surgery.

Common cardiovascular problems in the young: Part II. Hypertension, hypercholesterolemia and preparticipation screening of athletes.

Blood pressure should be measured during health maintenance visits in all children three years of age and older. Cholesterol levels should be obtained in children with a family history of hypercholesterolemia or premature coronary artery disease and in children with other risk factors, such as hypertension, smoking or obesity. Preparticipation screening for sports participation should include a detailed questionnaire regarding the athlete's personal or family history of syncope, sudden death or arrhythmia, as well as measurement of blood pressure, auscultation of the heart and evaluation of upper and lower extremity pulses.

Common cardiovascular problems in the young: Part I. Murmurs, chest pain, syncope and irregular rhythms.

Cardiovascular signs and symptoms in young people are common and usually represent variants of normal physiology. However, these signs and symptoms can also indicate the presence of important cardiovascular disorders. Innocent heart murmurs can be distinguished from pathologic murmurs by the lack of associated symptoms, as well as their loudness, timing and location. Although most chest pain in this age group is of musculoskeletal or psychogenic origin, cardiac causes can include pericarditis, aortic stenosis and coronary anomalies. Syncope is usually vasovagal in origin and has a benign prognosis. Sinus arrhythmia and isolated extrasystoles are the most common causes of irregular cardiac rhythms in the young. Multiform premature ventricular contractions, couplets and ventricular tachycardia may indicate underlying cardiac disease.

Natural course of isolated pulmonary valve stenosis in infants and children utilizing Doppler echocardiography.

Most natural history data regarding pulmonary stenosis (PS) were obtained from cardiac catheterization studies over 15 to 20 years ago. Selection bias in these studies often excluded patients with mild disease and infants. Today, Doppler echocardiography allows accurate serial assessments of stenotic lesions in patients of all ages. This study evaluates the natural history of PS utilizing serial Doppler examinations in the pediatric population. A total of 147 patients with PS and serial echocardiographic data were identified. Age at initial echocardiogram ranged from 2 days to 15 years, with a mean follow-up of 2.4 years. Sixteen of 56 patients (29%) initially evaluated within 1 month had a > or = 20 mm Hg increase in their peak systolic pressure gradient. Only 7 of 89 patients (8%) initially evaluated over 1 month had a > or = 20 mm Hg increase. Eleven of 40 newborn infants (28%) with mild obstruction had progression to moderate or severe PS compared with 10 of 68 patients (15%) initially evaluated over 1 month. Moderate PS in the newborn was also more likely to progress compared with older children. Of the 16 newborns with > or = 20 mm Hg increases, 8 developed the increase in < or = 6 months. In contrast, no patient aged >2 years whose initial gradient was <50 mm Hg developed severe PS. Mild PS may not be static, particularly in young infants. Progression in this age group occurs more often and more rapidly than in older infants and children.

Management of hypoplastic left heart syndrome in a consortium of university hospitals.

To determine current management of hypoplastic left heart syndrome, we utilized the discharge database of the University Hospital Consortium and obtained data on the surgical procedures, length of stay, hospital charges, and outcome for 636 neonates with this condition admitted to 40 member institutions from 1989 to 1993. Of the 636 patients, 95 (15%) were discharged without surgical intervention. A Norwood operation was performed in 222 (53% mortality) and transplantation in 40 (42% mortality). Median length of stay and hospital charges were 17 days and $57,418 for the Norwood procedure and 47 days and $126,695 for transplantation.

Noninvasive assessment of myocardial contractility, preload, and afterload in healthy newborn infants.

Assessment of ventricular contractility in the newborn infant using standard echocardiographic indexes can result in error due to the unique physiologic state that exists in the neonatal period. It has been suggested from animal and human studies that maturational alterations in contractility occur with birth and continue throughout infancy. To further investigate these developmental changes, 41 newborn infants aged 3 to 10 days and 37 children aged 3 to 18 years were evaluated with 2-dimensional and M-mode echocardiography. The rate-corrected velocity of circumferential fiber shortening (VCFc)-end-systolic wall stress (ESWS) relation was used as a load-independent estimate of contractility. Preload, afterload, and ventricular mass were also measured. Despite similar shortening fractions, the infant group had significantly higher mean VCFc and lower ESWS than the older age group (1.28 vs 1.08 circ/s and 30.2 vs 37.3 gm/m2, respectively). An inverse linear relation between VCFc and ESWS was found in both age groups. The y-intercept was higher in the infant group (p < 0.01), and the slope of the mean regression line was steeper than in the older children (p < 0.01). Ventricular mass in relation to body surface area increased with age. We conclude that (1) newborn infants have a higher basal contractile state that cannot be accounted for by lower afterload, (2) myocardial performance is more sensitive to afterload in the immature heart, and (3) shortening fraction may underestimate ventricular function in the newborn.

Myocardial contrast echocardiography and the transmural distribution of flow: a critical appraisal during myocardial ischemia not associated with infarction.

OBJECTIVES: This study was undertaken to determine whether myocardial contrast echocardiography can be used to estimate the transmural distribution of flow. BACKGROUND: Myocardial contrast echocardiography has been shown to reliably measure average transmural blood flow during myocardial ischemia. However, there is controversy regarding its ability to determine the transmural distribution of flow. METHODS: The transmural distribution of flow was measured in 21 open chest anesthetized dogs with use of radiolabeled microspheres and sonicated albumin microbubbles (mean size 4.5 microns). In the 11 Group I dogs, myocardial contrast echocardiography was performed at baseline and during left anterior descending artery stenosis. In five of these dogs, it was also performed during left circumflex artery stenosis. In these dogs large (mean 12 microns) hand-agitated bubbles were also used. In the five Group II dogs, myocardial contrast echocardiography was performed before and 45 s after intracoronary injection of 6 mg of papaverine in the presence of a critical left circumflex artery stenosis. The five Group III dogs were studied during cardiopulmonary bypass at baseline and during left anterior descending artery stenosis. Off-line image analysis of the echocardiographic images was performed and time-intensity curves obtained from these images were correlated with radiolabeled microsphere-derived flows. RESULTS: The ratios of the parameters derived from the endocardium and epicardium during myocardial contrast echocardiography were found to correlate poorly (ranging from R2 = 0 to R2 = 0.35) with radiolabeled microsphere-derived endocardial/epicardial flow ratios over a wide range of flow ratios (0.01 to 2.58). These results were not influenced either by the location of the regions of interest (left anterior descending vs. left circumflex artery bed) or by the size of the bubbles (4.5 vs. 12 microns). CONCLUSIONS: Myocardial contrast echocardiography cannot be used to assess the transmural distribution of flow during myocardial ischemia not associated with infarction.

Pleuroperitoneal shunts for refractory chylothorax after operation for congenital heart disease.

Between 1980 and 1990, 10 of 12 children with a symptomatic chylothorax after operation for congenital heart disease failed to respond to traditional medical therapy (thoracentesis, tube thoracostomy, low-fat diet). All 10 patients underwent placement of a pleuroperitoneal shunt, with complete resolution of the chylothorax in 9 patients (90%). Cardiac catheterization, performed before placement of the pleuroperitoneal shunt in 5 patients, demonstrated elevated right atrial pressure in all patients (range, 10 to 25 mm Hg). The pleuroperitoneal shunt functioned effectively in 4 patients with moderately elevated right atrial pressures (range, 10 to 16 mm Hg; median, 13.5 mm Hg) but not in 1 patient with a right atrial pressure of 25 mm Hg. Pleuroperitoneal shunting as treatment for chylothorax after operation for congenital heart disease is safe and effective, even in the face of moderate elevations in right atrial pressure.

Echocardiographic determination of aortic and pulmonary valve areas in subjects with normal hearts.

Two-dimensional and Doppler echocardiography were performed in 70 subjects (aged 1 day to 16 years, body surface area from 0.08 to 2.1 m2) to determine aortic and pulmonary valve areas in normal children and adolescents. Valve areas were determined by the continuity equation using echo-determined ventricular outflow tract diameters and Doppler-determined flow velocities from the outflow tracts and corresponding great arteries. Left ventricular outflow tract diameter ranged from 0.3 to 2.2 cm and right ventricular outflow tract diameter from 0.4 to 2.8 cm. Outflow tract diameters were linearly related to the square root of body surface area. Flow velocity increased from a mean of 0.75 m/s in the left ventricular outflow tract to 1.12 m/s in the aorta and from 0.56 m/s in the right ventricular outflow tract to 0.89 m/s in the pulmonary artery. Flow velocities were unrelated to body size. Valve areas were linearly related to body surface area (r = 0.88 and 0.80 for the aortic and pulmonary valves, respectively). Mean aortic and pulmonary valve area indexes were 1.33 cm2/m2 and 1.70 cm2/m2, respectively. The data provide normal values for echocardiographically determined valve areas and validate the practice of indexing valve area for body surface area.